Conventionally, there has been known a nanofiber manufacturing apparatus having a collector member with a specified voltage applied thereto, and a nozzle which is located at a specified distance from the collector member and to which a voltage having a specified voltage difference to the collector member is applied. The nozzle with a voltage applied thereto electrically charges and simultaneously delivers out a raw material liquid (high-polymer solution) of nanofiber toward the collector member. The delivered-out raw material liquid, while dried with its solvent evaporating, goes toward the collector member. While moving toward the collector member, the raw material liquid has the solvent increasingly evaporating so as to cause electrostatic explosions, being drawn and finally formed into nanofiber. The formed nanofiber is deposited on a base sheet placed on the collector member by electrostatic collection by the collector member. As the solvent adhering to the nanofiber deposited on the base sheet has fully been evaporated, a base sheet with a nanofiber layer formed thereon is completed.
As the collector member of the collecting device acting for electrostatic collection and deposition of nanofiber on the base sheet, those in various modes have been known. A nanofiber manufacturing apparatus described in PTL 1 employs an electrically conductive belt as the collector member. Nanofiber is deposited on a base sheet on the conductive belt. A voltage is applied to the conductive belt indirectly with a voltage applied to a roll that supports the conductive belt.
A nanofiber manufacturing apparatus described in PTL 2 employs an electrically conductive plate-shaped collector member. This conductive plate-shaped collector member has a plurality of holes formed for blowing out air toward the base sheet on the conductive plate-shaped collector member.
Also, a nanofiber manufacturing apparatus described in PTL 3 employs a collector member composed of a plurality of electrodes, which are in contact with the base sheet, and an endless resin belt which supports the electrodes.
Still also, a nanofiber manufacturing apparatus described in PTL 4 employs, as the collector member, a plurality of brush-like electrodes being in sliding contact with the surface of the base sheet.